You have been passed over for two promotions while a male colleague (who joined the company after you) steams up the corporate ladder. He's been on more training courses than you and also plays golf with the boss. Funny that. You're both at the same level but he's on a bigger salary. If you were a man, you're convinced you would be treated differently. Yes, it's unfair and it's almost certainly discrimination, but how could you ever prove it? Keep a diary and record when the exclusion takes place? "Tuesday evening: my boss asked 'him' to the pub to discuss this afternoon's staff meeting" is hardly the stuff of courtroom drama.

Yet, any solicitor will say it's the accumulation of minor details like these that can build up a case of real sex discrimination. They will also tell you that the reality of trying to pursue such a case is harrowing, costly and time-consuming. Would it really be worth the hassle and the heartache to go to such lengths? Much easier, you may well decide, to bide your time and find another job.

PC Paula Wilson has retreated to lick her wounds after losing her sex discrimination case last week. Her defeat will have confirmed the fears of other women who may have considered taking similar action but chose not to stick their head above the parapet. As the first female officer to take a case of sex bias against Northumbria police to tribunal stage, it is a fair bet that she did not make the decision lightly. Yet in her second week at court, she withdrew her allegations that she had been overlooked for overtime and training. Like many other women, she may not have realised just how harrowing the whole experience would be.

"It was such an uphill battle, I didn't feel it was worth it," says Wendy, 35, who was a marketing manager for a travel company. Two years ago, she complained about her boss who, she argued, passed her over for promotion and training when he discovered she was three months pregnant. "After I told him, he virtually ignored me and began to give my male colleague all the best projects and biggest accounts. I wasn't part of a union so I knew I'd have no support."

Wendy consulted a solicitor. "She advised me exactly what I could expect in court, how long it could take and the sort of detailed evidence I'd have to produce. I went away and thought about it for a long time. I realised what a minefield the whole thing was and I got scared about my employment chances after I left his company. I just couldn't go through with it," she admits.

If a woman has a really strong discrimination case, her best bet is to ask the Equal Opportunities Commission to take it on. The problem is that they are underfunded - last year they could only afford to accept around 70 cases. That leaves the majority of women fighting as lone individuals. Only the very strong examples - such as PC Kay Kellaway, who won her case against Thames Valley police in September - really stand a chance. Others find it more difficult to fight back. Cydena Fleming, a police inspector, was described in the papers as "a broken shadow of her former self... gaunt and receiving medical treatment," after she took her employers to court. Her case is still pending, but you wonder if the litigation is really worth the emotional trauma.

Solicitor Catherine Tailby has wide experience of sex discrimination cases, and confirms that many women are discouraged from speaking out and confronting the system. She thinks this is understandable. "I have a lot of queries about maternity issues. Yes, a lot of women do feel put off from taking it to court. It is intimidating. People can say things that will be unpalatable. They will fight it out in the open and downplay your abilities to prove it wasn't sex discrimination."

According to the latest tribunal statistics, only 5.9 per cent of sex discrimination cases presented were successful during 1995-96. Forty per cent were withdrawn and a further 40 were settled by ACAS. Michelle Sedgwick, legal officer at the trade union Unison, says, "There are hurdles. One problem is the way cases affect people. It's obviously a painful and distressing experience. It strikes at the core of one's identity. Sometimes a tribunal will categorise women as being hysterical. The perception is still that women who complain about things are a problem."

Another obstacle for women, says Tailby, is the "burden of proof". It means they must prove their claims, rather than the employerhaving to prove he wasn't sexually discriminating against her. "There is talk at a European level of reversing this law," she says. The focus of proof could switch from accuser to accused. If this happened, certainly the woman would feel less victimised by the process. As it stands, the unspoken message can often be that her word is somehow in doubt; that she can't be trusted.

Tailby says, "I've had people who've collapsed because the whole experience was so distressing. They couldn't stand it any more, especially if they're suing an employer and still working with them."

That's if you're lucky enough to keep a job. Jean, 34, who worked in finance, was sacked last year when she accused her boss of discrimination. For a long time she was passed over for promotion, then her employer offered her a new job with one simple proviso - that she slept with him. "I really never thought I'd be in this situation ever in my life," says Jean, now hoping to settle her case out of court. "Basically, they want to go through your knicker drawer. It's all right in the States where you can be awarded loads of money, but here the risk of losing and paying court costs just isn't worth it." Neither was the very real threat of losing her professional reputation. "If I was leaving the country, fine, but if you are looking for other jobs in the same field then don't even think about it. Apart from that, the whole thing would take too long."

Five years down the line and Katie, 42, who used to be an engineer, is still fighting her sex discrimination case. As a single mother, she was forced to leave her job when they changed her working hours and refused to remain flexible. "There was no chance of keeping my job. They just didn't want women with children working there. It's been re-designed for single people. It's like rape, in that a woman must prove that she's been attacked rather than the rapist proving he didn't commit the crime. Why is it up to us to prove it?" One of the worst moments during the tribunal was hearing herself described by her boss. "He tried to portray me as a weak women and said he used to comfort me when I was crying - as if I'd ever behave like that. It made my stomach turn."

When a case gets this personal and confrontational you wonder whether the process has failed the victim before it's begun. Jo Gardner, campaigns manager at the Industrial Society, believes litigation isn't always the answer. "Let's have fewer court cases," she argues, "and better practice. It's not the answer to make case-bringing easier. It's better to explain the benefits of being good practitioners to begin with, and to get back to business with the least amount of aggro."

Except that "better practice" often results from legal precedents. Katie says, "I'm fighting for what is rightfully mine - it makes me feel good." She still believes that however daunting a tribunal can be, if you succeed it's still the best and most effective means of setting the record straight.

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